| Place Name | Martinsburg |
| Place Type | City |
| ZIP Code(s) | 52568 |
| County | Keokuk County |
| Area Code(s) | 641 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 166 |
| Population Growth Rate (2010-19) | -1.79% |
| Majority Ethnicity | White 96.55% |
| US Congressional District(s) | Iowa 2nd |
| State House Districts | 78 |
| State Senate Districts | 39 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 96.55% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 3.45% |